package observer.weatherStation;

public class HeatIndexDisplay implements Observer, DisplayElement {
	
	private float temperature, humidity;
	private Subject weatherData;
	
	public HeatIndexDisplay(Subject weatherData) {
		this.weatherData = weatherData;
		weatherData.registerObserver(this);
	}

	@Override
	public void update(float temp, float humidity, float pressure) {
		this.temperature = temp;
		this.humidity = humidity;
		this.display();
	}

	@Override
	public void display() {
		System.out.println("Heat index is " + computeHeatIndex(this.temperature, this.humidity));		
	}
	
	private float computeHeatIndex(float t, float rh) {
		float index = (float)((16.923 + (0.185212 * t) + (5.37941 * rh) - (0.100254 * t * rh) + 
				(0.00941695 * (t * t)) + (0.00728898 * (rh * rh)) +
				(0.000345372 * (t * t * rh)) - (0.000814971 * (t * rh * rh)) +
				(0.0000102102 * (t * t * rh * rh)) - (0.000038646 * (t * t * t)) + (0.0000291583 *  
				(rh * rh * rh)) + (0.00000142721 * (t * t * t * rh)) +
				(0.000000197483 * (t * rh * rh * rh)) - (0.0000000218429 * (t * t * t * rh * rh)) +     
				0.000000000843296 * (t * t * rh * rh * rh)) -
				(0.0000000000481975 * (t * t * t * rh * rh * rh)));
		return index;
    }
	
}
